中文摘要：

设计了干涉条纹形状对悬臂角度变化不敏感的干涉光路系统,针对实际干涉条纹光电转换信号的特点,提出了对难以保证正交化的两路信号进行实时椭圆拟合的方法。应用椭圆拟合及换算参数的结果,推导了干涉条纹相位变化的理论公式。最后,根据相位量与振动位移量的关系,以及振动位移连续性的特点,通过直接解包裹的衔接算法,得到了最终振动位移量。实验表明,该方法在保证足够采样频率的条件下,无需额外硬件计数电路,就能完成微悬臂振动位移的干涉量级精度的测量。

英文摘要：

This paper designed interference measurement system which the stripe shape was less sensitive to cantilever＇s changing angles. Then analysing the characteristics of two-photoelectric re- ceiving interference signals which were difficult to guarantee orthogonalization, a real-time ellipse fit- ting method was proposed. Using the ellipse fitting method and the conversion results, the theoretical formula of interference fringe phase change could be derived. Finally, according to the relationship be- tween the phase and vibration displacement, and the property of vibration displacement~s continuity, vibration displacement quantity could be obtained by using unwrapping algorithm. The results show that this method can achieve measurement level of interference precision order without additional hardware processing circuit wnder the conditions of the sufficient samDling freauencv.